Lock washer



May 30, 1933. c; e. OLSON 1,911,334

LOCK WASHER Filed July 14, 1930 26 2; Ga) awson- 25 siliently Patented May 30, 1933 UNITED STATES PATENT OFFICE CARL G. OLSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO SHAKE-PROOF LOCK WASHER COMPANY, OF CHICAGO, ILLINOIS, A.CORPORATION OF DELAWARE LOCK WASHER Application filed July 14,

of spaced conductor sections, and a bolt is employed to pivotally and clampingly secure the knife between these conductor sections.

It is one of the objects of my present invention to provide a lock washer, which is particularly adaptable to secure these bolts and nuts associated therewith against loosen- In switch constructions, as above set forth,

the conductor sections which support an clampingly engage the switch knife, must not be clamped against said knife with suificient force to inhibit the pivotal movement thereof. -Therefore, I propose to provide a lock washer of the spring type that will re or yieldin ly bear againstthe outer surface of the conductor section upon which the switch knife is pivoted.

More specifically, my invention contemplatesthe provision of a spring type of lock 0 washer, which is provided with teeth or prongs for lockingly engaging the conductor section and also prongs for lockingly engaging the nut which is employed to clamp said washer in position.

A still further object of my invention is to provide an annular lock washer of dished construction, provided with a plurality of 4 external prongs or teeth for lockingly engaging a fixed member, such as a conductor section and a plurality of internal teeth for lockin ly engaging a nut, the clamping action 0 the nut serving to flatten the washer and thereby urge the imbedded external teeth radially.

The foregoing and numerous other 0b- 'ects will be more apparent from the followmg detailed description, when considered in connection with the accompanying drawing, whereinp Figure 1 is a fragmentary plan view of a 1930. Serial No. 467,649.

view taken substantially along the line 4-4 a of Figure 3;

Figure 5 is a side elevational view of a lock washer equipped with external locking teeth of modified construction;

Figure 6 is also a side elevational view of a lock washer having a modified external tooth construction;

Figure 7 is another modification disclosing a spring type washer equipped with exd ternal locking teeth, which differ in structural characteristics from the teeth shown in the other washers;

Figure 8 is a transverse sectional view taken substantially along the line 88 of Figure 7 Figure 9 discloses a lock washer of the type shown in Figures 1 to 4 inclusive, associated with the work, the lock washer being shown in position prior to the clamping thereof against the work surface; and

Figure 10 is a view similar to Figure 9, disclosingthe position occupied by the washer after it has been clamped and locked between the work surface and the clamping nut.

Referring now to the drawing more in de tail wherein like numerals have been employed to designate similar parts throughout the various figures, it will be seen that one embodiment of my invention includes a spring type lock washer,'which I have -desig-' nated generally by the'numeral 12, Figures 1 to 4 inclusive and Figures 9 and 10. This lock washer 12 includes an annular body portion 14, which is equipped with integral external prongs 16 and a plurality of internal twisted locking prongs or teeth 18; Each of the prongs 16 is formed with work engaging teeth 20, which are adapted, when a clamping force is exerted axially of the washer, to imbed themselves within the work.

It will be observed that the washer is of a dished construction, or what might be referred to as a concavo-convex construction. The internal twisted teeth 18 are also adapt ed to imbed themselves within a work plece, and in order to more clearly disclose one practical application of a lock washer of my improved design, I have shown the-same 1n operative association with a knifeswitch 1n Flgures 1 and 2.

The particular type of knife switch shown in the drawing includes a blade or knife member 23, which is pivotally mounted on a bolt 24, and this bolt 24 extends through a pair of spaced conductor sections 26. The conductor sections 26 may be of suitable integral 1 construction as is conventionally employed on switches of the type shown and is mounted upon a suitable base 28. The threaded extremity of the bolt or screw 24 is adapted to receive a clamping nut 30, and the washer 12 is positioned between the nut 30 and one of the conductor sections 26', as clearly shown in Figures 1 and 2 and also Figures 9 and In Figure 9 I have shown the washer 12 in position between the nut 30 and the work iece orconductor section 26 in readiness to be clamped therebetween. As the nut 30 is screwed against the teeth or prongs .18, the external teeth 20 become imbedded within the work piece 26 and are urged outwardly to the position shown in Figure 10. Thus,

' it will be apparent that when the lock washor is positioned as shown in Figure 10, the teeth 20 will secure said washer against relative movement with respect to the work iece 26, and the prongs or teeth 18 will lockingly imbed themselves within the adjacent face of the nut 30 so as to secure said nut against rotation with respect to the screw or bolt 24. In this manner the lock washer serves as an effective means for positively securing the bolt and nut against loosening.

. Obviously, the. clamping action of the bolt and nut should not be suflicient to impair the manual manipulation of the switch knife 22. In this instance the yieldable or resilientna ture of the lock washer, which results from its concavo-convex construction, precludes the positive clamping action of the nut against the conductor section 26. As shown in Figure 10, when the nut 30 is secured in position, the washer resiliently and lockingly bears against the work piece or conductor section 26. When the washer 12 is secured in this position, the switch knife 22 may be successively shifted about its pivotal support without the slightest tendency of loosening the clamping nut 30. I

Obviously my invention is not limited to the particular design of washer shown in Figures 1 to 4 inclusive, and in order to suggest other modifications which come within the scope of my invention, I have shown m'odi- 4. The external teeth of the washer 12a,

however, are formed with V-shaped prongs 20a which provide work engaging sharp teeth .or points. The principle of operation of the washer 12a is similar in every respect to the washer previously described.

In Figure 6 I have designated a modified washer construction by a numeral 126, and this construction differs from the other constructions in the particular type of external prongs, which I have designated by a numeral 16?). These prongs 16?) are provided with locking teeth 20?).

Figures 7 and 8 disclose a further modified washer construction designated generally by a numeral 120. This washer 120 is provided with modified prongs 160, each prong being formed with a plurality of work engaging teeth or points 200. Internal teeth 180 also differ from the twisted type of internal teeth just described and present a ratchet-like construction. I

From the foregoing it will be apparent that my invention contemplates the provision of a lock washer construction of improved practical design, which is of a spring or resilient nature to particularly adapt the device for use in clamping a pivoted member between a pair of supporting sections, such as the conductor sections 26. The washer may be formed by practicing conventional machine shop methods and is adaptable for a wide range of uses.

The resilient feature of my improved washer enables the external teeth or prongs to form radial grooves 32 within the work piece, as shown in Figure 10, thereby enabling a certain amount of movement between the associated parts axially of the clamping bolt without permitting the dislodgment of the external teethfrom said radial grooves. It-

should be noted that the washer is so designed as to permit free rotation of the nut in a direction to tighten the same, but prevents said nut from rotating in the opposite direction.

The invention is in no sense limited to the particular application shown in the drawing, nor is the invention limited to the particular tooth structures shown in. the drawing, but.

is capable of many other modifications and changes without departing from the spirit work engaging teeth, the external prongs being adapted to move outwardly in response to a clamping force exerted axially of the washer and thereby cut a locking groove in the work.

2. A look washer comprised of resilient sheet stock including an annular body portion, a plurality of teeth alon the inner margin warped out of the plane t ereof for lockingly engaging the clamping surface of a rotary clamping member such as a nut or screw head, and an outer toothed marginal edge adapted to engage a workpiece positioned on the side of the washer oppositely disposed from said rotary clamping member, said toothed outer edge being s aced radiall from the axis of the washer a istance whic is suflicient to position said edge beyond and thereby avoid interference with the surface of said rotary clamping member, said internal teeth and adjacent section of the body portion being normall spaced from the workpiece engaged by t e outer margin and adaptedto yield toward said workpiece when the rotary clamping surface is tightened against the said inner teeth, said outer teeth being adapted to cut a locking groove in the workpiece in response to a tightening force exerted axially of the washer.

In witness whereof, I have hereunto subscribed my name.

CARL G. OLSON. 

